Worldwide sperm quality variations between 2000 and 2020: a scoping review

There is a scarcity of research on male infertility and semen quality worldwide, notably in the Middle East and North Africa (MENA) region. This lack includes temporal comparisons of seminal parameters over decades. The aim of this scoping review is to summarize the articles, published between January 1, 2000, and December 31, 2020, which discuss and describe human semen quality and/or sperm quality in different countries, and/or their alternating patterns through time. The search was done on PubMed, using the following keywords: (((semen[Title/Abstract]) OR (SFA[Title/Abstract])) OR (sperm[Title/Abstract])) AND (country name[Title/Abstract]) with 195 world countries put in the “country name” field one by one along with other filters. The abstracts that fulfilled the inclusion criteria were read thoroughly and summarized. In conclusion, although some semen parameters appear to be stable, semen quality has deteriorated over time. Therefore, various countries must conduct research to characterize their semen quality and its altering patterns throughout time to reach a thorough conclusion.